Ultrasound probes come in varying shapes and sizes for different applications. The probes you use as an OB/GYN will differ from those used by a vet. Each type of ultrasound probe comes with its own specifications for creating high-quality images on different parts of the human body or animal’s bodies.
Ultrasound probes are used in two ways – passed over the body’s surface or inserted into an orifice. They are known as external and internal probes, respectively.
Let’s discuss the five most common ultrasound probe types and their main uses.
5 Types of Ultrasound Probes
1. Linear Ultrasound Probes
Linear transducers are named as such because they have a linear piezoelectric arrangement.
The linear type ultrasound probe has a rectangular beam. They are also known to have a better-than-average near-field resolution which makes them useful for many applications where you need high-quality images.
Several clinical applications will use a linear type probe – for example, vascular or breast – and the application will determine the frequency and footprint of the probe.
Linear probes allow for both 2D and 3D imaging. Depending on which you need, the frequency will vary. Typically, 2D probes have a wide footprint and a central frequency of 2.5Mhz – 12Mhz. In contrast, 3D probes have a wide footprint and a central frequency of 7.5Mhz – 11Mhz.
2. Convex Ultrasound Probes
Convex-type probes are often also referred to as curved ultrasound probes. They have a piezoelectric crystal arrangement that is curvilinear. The shape of the beam created by this probe means that the main application of convex probes is for deeper organ imaging.
Typically 3D imaging convex probes have a wide footprint and a central frequency of 3.5MHz – 6.5MHz. For 2D probes, they also have a wide footprint but have a central frequency is 2.5MHz – 7.5MHz.
3. Phased Array Ultrasound Probes
Another common type of ultrasound probe is the phased array. The crystals of this type of probe are arranged in a “stacked” construction, also known as a phased array.
The beam of a phased array is narrow, a triangle shape, and the near-field resolution is poorer than with many other types of probes.
It has a small footprint and typically a frequency between 2 MHz – 6 MHz.
The most common uses for a phased array probe are cardiac and trans-cranial examinations.
4. Pencil Ultrasound Probes
Pencil probes, also known as CW Doppler probes, are typically used to measure blood flow and sound speed in blood.
It has a small footprint and uses a low frequency of between 2Mhz– 8Mhz.
5. Endocavitary Ultrasound Probes
This type of ultrasound probe is used for performing internal examinations of the patient.
Endocavitary probes are designed to fit within specific body orifices. Therefore they vary in size and shape, depending on the application. For example, one common type is the endovaginal probe.
Typically, endocavitary probes have small footprints, and the frequency varies in the range of 3.5Mhz – 11.5Mhz.
Understanding Probe Types Is Essential
There are lots of types of ultrasound probes that all have their specific application. The first three on the list are the ones that you are most likely to come across and the last two are less commonly used.
Understanding the types of probes available and their specific applications can help you take care of your medical equipment by ensuring that it is always used properly.